Viewing archive of Sunday, 28 November 1999
Solar activity report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 1999 Nov 28 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 332 Issued at 2200Z on 28 NOV 1999IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z SOLAR ACTIVITY WAS MODERATE. REGION 8771 (S15W85)
PRODUCED AN M3/SN AT 28/0146UT AND AN M1/SF AT 28/0557UT. LIMB
OBSERVATIONS SUGGESTS THAT THIS REGION WAS ALSO RESPONSIBLE FOR A
LONG-DURATION M1 X-RAY FLARE WHICH STARTED AT 28/1800UT AND PEAKED
AT 1917UT. LIMB PROXIMITY IS MAKING OBSERVATIONS OF THIS REGION
DIFFICULT. A NUMBER OF OTHER ACTIVE REGIONS PRODUCED SMALL FLARES,
INCLUDING 8773 (S12W71), 8778 (S14W33), AND 8781 (S13E22).
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE WITH A CHANCE OF A MAJOR FLARE FROM REGION 8771 BEFORE IT
COMPLETELY DEPARTS THE VISIBLE DISK.
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY QUIET TO UNSETTLED. ACTIVITY LEVELS MAY BE
ENHANCED DURING THE 3-DAY FORECAST PERIOD DUE TO A PARTIAL-HALO CME
ON NOV 26 AND/OR A HIGH-SPEED CORONAL HOLE STREAM.
III. Event Probabilities 29 NOV to 01 DEC
| Class M | 60% | 50% | 40% |
| Class X | 10% | 05% | 01% |
| Proton | 05% | 05% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 28 NOV 175 Predicted 29 NOV-01 DEC 160/150/145 90 Day Mean 28 NOV 164
V. Geomagnetic A Indices
OBSERVED AFR/AP 27 NOV 001/003 ESTIMATED AFR/AP 28 NOV 008/010 PREDICTED AFR/AP 29 NOV-01 DEC 010/012-010/015-010/010
VI. Geomagnetic Activity Probabilities 29 NOV to 01 DEC
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 10% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 05% | 05% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 10% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 05% | 05% | 05% |
All times in UTC
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